Automatic Test Equipment (ATE) is commonly used within the field of electronic chip manufacturing for the purposes of testing electronic components. ATE systems both reduce the amount of time spent on testing devices to ensure that the device functions as designed and serve as a diagnostic tool to determine the presence of faulty components within a given device before it reaches the consumer.
In general, components, for example, electronic components or devices, micro-electronic chips, memory chips or other integrated circuits (IC), are usually tested before they are delivered to a customer. Testing may be performed in order to prove and ensure the correct functional capability of the devices. The tests are usually performed by means of an automated test equipment or test system. Examples for such ATE are the Advantest V93000 SOC for testing system on a chip and system on a package, the V93000 HSM high speed memory tester (HSM) for testing high speed memory devices and the Advantest V5000 series. The first is a platform for testing systems on a chip, systems on a package and high-speed memory devices. The latter is for testing memory devices including flash memory and multi-chip packages at wafer sort and final test.
During testing these devices under test (DUTs) are exposed to various types of stimulus signals from an ATE. The responses from such devices under test are measured, processed and compared to an expected response by the ATE. Testing may be carried out by automated test equipment, which usually performs testing according to a device specific test program or test flow. Such an automatic test system may comprise different drivers for driving certain stimuli to a DUT, in order to stimulate a certain expected response from the device under test. Receiver units of the ATE may analyze the response and generate a desired output regarding the performance of the measured device.
ATE systems can perform a number of test functions on a device under test (DUT) through the use of test signals transmitted to and coming from the DUT. The DUT interface board is docked to the ATE system by a mechanical system that secures the board and makes electrical contact using, for example, a interconnect system of pogo blocks and blind mate RF SMP connectors. An SMP connector offers a typical frequency range of DC to 40 GHz and is commonly used in miniaturized high frequency coaxial modules. The ATE can interface to and test semiconductor devices in package or wafer form.
ATE systems can perform a number of test functions on a device under test (DUT) through the use of test signals transmitted to and from the DUT. Conventional ATE systems are very complex electronic systems and generally include resources such as digitizers, computers, and digital control hardware to analyze the resulting signals transmitted to or from the DUT to the tester testing session. Modulated test signals to or from the DUT at high frequencies are commonly analyzed for the modulation errors and characteristics of the DUT. Modern mobile phone transceivers are a good example of how the ATE can be employed to test modulation errors and characteristics of the DUT transceivers. Hence, modern ATE systems need to analyze the modulated signals of common lower frequency DUTs such as cellular telephone and Bluetooth using software libraries (API). This requires that a modulated signal is sent to the device or the transmitter itself provides the modulation. It is common for a phase shifter test to be incorporated in the design of the receivers and transmitters for beam-forming and signal identification. However, phase shifters cannot be easily tested without a full vector analyzer available, which is difficult to implement in ATE or to apply effectively in a production environment to a transmitted signal modified by the phase shifter.
Automotive radar applications incorporate phase shifters into the DUT, which requires a different approach for testing. These phase shifters can be controlled by external commands sent to the device. Setting a particular phase change in a high frequency transmitter causes the phase changes that may be required for a beam forming application, and the changes must be measured accurately and quickly. Automotive radar transmitters and receivers may both have phase shifters commonly incorporated within them. Testing each transmitter or receiver requires that each state (setting) of the phase of the phase shifter is tested and recorded against the expected value set by the control programming. This process can be time-consuming and inefficient. Further, as mentioned above, the bench equipment required to perform this testing can be expensive and may not be as useful as connecting to the DUTs may be impractical (e.g., there may be no ports available). Additionally, the bench equipment must create a known reference signal (with a known phase and timing) so that the output signal from the DUT phase shifter can be compared against it. Furthermore, when multiple signal paths need to be tested on a DUT, testing each and every phase shifter setting can be time-prohibitive. As a result, prior methods of testing DUT phase shifters, which were quite difficult to implement and capital intensive were typically performed only on the laboratory bench.